from the little i did with artifice usally ended up with alittle less then half the mats back.
but usally lost the blue quality mats, some times when re-eng the blue hilts id get just the blue mat but none of the low crystals.
so yes youll get mats back but at a loss. its getting enough blue mats to make blue items that was sometimes the pain.
just test it out on afew items and youll see how it works.
it was also buggy in beta for me, most the time i couldnt re-eng cuz the button was gone lol.